Carton forming apparatus with simultaneously ignited heaters

ABSTRACT

An apparatus for forming cartons comprises feeding means, including a pivoted suction cup and cooperating vacuum belt conveying means, for individually feeding carton blanks to a forming means. Such forming means comprises a rotary table having a plurality of female forming dies radially positioned thereon. A ram-type male die is reciprocally mounted above the table to cooperate with each forming die to form the carton blank into tray form. Gas burner type heaters are mounted adjacent to the table for simultaneous ignition to discharge heated air onto partially folded corners of a polyethylene-coated carbon blank prior to when it is fully formed in the forming die. After the corners are compressed and sealed, stripping means engage the formed carton to move it onto a discharge conveyor.

United States Patent 1191 Lefebvre et al.

CARTON FORMING APPARATUS WITH SIMULTANEOUSLY IGNITED HEATERS Inventors:Alfred B. Lefebvre, Danville;

Helmut E. W. Masch, San Jose; Louis Robert, San Mateo; Hugh B. Morse,San Jose, all of Calif.

Assignee: Fireboard Corporation, San

Francisco, Calif.

Filed: Dec. 13, 1971 Appl. No.: 207,057

Related US. Application Data Continuation-impart of Ser. No. 187,170,Oct. 6, 1971, abandoned, which is a division of Ser. No. 32,836, April29, 1970, Pat. No. 3,648,573.

1111. c1. F23q 9/00 Field of Search 431/6, 191, 192, 283, 286, 431/157,158; 285/9, 19, 20; 53/375 References Cited UNITED STATES PATENTS 7/1950Slayter et a1 431/158 X 4/1966 Smith et a1 431/6 June 18, 1974 3,315,6554/1967 Stone et a1 431/283 X 3,421,416 1/1969 Benzon-Peterson 83/51.13,713,952 l/1973 Schafer et a] 53/375 Primary Examiner-William F. ODeaAssistant Examiner--William C. Anderson Attorney, Agent, orFirmPhi1lips, Moore, Weissenberger, Lempio & Strabala [5 7] ABSTRACT Anapparatus for forming cartons comprises feeding means, including apivoted suction cup and cooperating vacuum belt conveying means, forindividually feeding carton blanks to a forming means. Such formingmeans comprises a rotary table having a plurality of female forming diesradially positioned thereon. A ram-type male die is reciprocally mountedabove the table to cooperate with each forming die to form the cartonblank into tray form. Gas burner type heaters are mounted adjacent tothe table for simultaneous ignition to discharge heated air ontopartially folded comers of a polyethylene-coated carbon blank prior towhen it is fully formed in the forming die. After the comers arecompressed and sealed, stripping means engage the formed carton to moveit onto a discharge conveyor.

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PAIENTEiIJuI 18 1014 0N wE N UE NON m now 08 85 CARTON FORMING APPARATUSWITH SIMULTANEOUSLY IGNITED HEATERS CROSS-REFERENCE TO RELATEDAPPLICATIONS This application is a Continuation-in-Part of US. Patentapplication Ser. No. 187,170, filed Oct. 6, 1971, now abandoned, whichwas a Divisional Application of US. Patent application Ser. No. 32,836,filed Apr. 29, 1970 now US. Pat. No. 3,648,573.

BACKGROUND OF THE INVENTION This invention relates to the packaging artsand more-- SUMMARY AND OBJECTS OF THIS INVENTION An object of thisinvention is to overcome the above, briefly described problems byproviding a heater assembly and method for expeditiously, efficientlyand economically discharging a heated fluid onto scalable carton flaps.The heater assembly is particularly useful for discharging a heatedfluid onto folded corners of a carton blank to activate a pre-coatedadhesive prior to final sealing. Such assembly comprises a plurality ofheaters connected together for simultaneous ignition of a gaseous fuelcommunicated thereto.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects of this invention willbecome apparent from the following description and accompanying drawingswherein:

FIG. 1 is an isometric view of a preferred apparatus embodiment of thisinvention;

FIG. 2 is a top plan view of a carton blank, taken in the direction ofarrows 2-2 in FIG. 7, adapted to be formed into the carton shown inFIGS. 3-5 by the FIG. 1 apparatus;

FIG. 6 is a partially sectioned and enlarged top plan view of the FIG. 1apparatus, taken in the direction of arrows 66 in FIG. 1;

FIG. 7 is an enlarged sectional view taken in the direction of arrows 77in FIG. 6 with parts brokenaway for clarification purposes;

FIG. 8 is a sectional view taken in the direction of arrows 88 in FIG.15;

FIGS. 9 and 10 schematically illustrate portions of drive systemsemployed in the FIG. 1 apparatus, with FIG. 9 being taken in thedirection of arrows 99 in FIG. 6;

FIGS. 11 and 12 schematically illustrate the FIG. 1 apparatus in variousmodes of its carton forming opera tion;

FIGS. 13 and 14 are enlarged, top plan views of a forming die employedin the FIG. 1 apparatus with a carton blank being sequentiallypositioned thereon;

FIG. 15 is an enlarged, sectional view generally taken in the directionof arrows 15-15 in FIG. 6;

FIG. 16 is a partially sectioned and enlarged isometric view generalltaken in the direction of arrows 16- 16 in FIG. 6, illustrating a cartonstrippingmeans employed in the FIG. 1 apparatus;

FIG. 17 is a view generally taken in the direction of arrows 17-17 inFIGS. 6 and 16;

FIG. 18 is a view taken in the direction of arrows l8-l8 in FIG. 17;

FIG. 19 is a partially sectioned top plan view of a plurality ofheaters, similar to those illustrated in FIG. 8; and

FIGS. 20 and 21 are sectioned views taken in the direction of arrows20-20 and 21-21 in FIG. 19, respectively.

DESCRIPTION OF PREFERRED APPARATUS EMBODIMENT The FIG. 1 apparatuscomprises, in series, a feeding station 20 for individually conveyingcarton blanks C to a forming station 21 and a discharge station 22 forremoving the formed cartons therefrom. The FIG. 2 onepiece paperboardcarton blank is preferably coated on both sides with a suitable laminantplastic coating, such as polyethylene, polyvinylidene chloride or othersuitable heat sensitive coating which will reactivate (melt) at hightemperatures such as 500F. The blank may be suitably cut and scored tocomprise a bottom panel P side panels P and P and front and rear panelsP, and P A top panel or cover flap F 1 is hingedly connected at ascoreline to the top edge of rear panel P whereas vertically disposedminor flaps F F and F are connected in a similar manner to panels P Pand P respectively. A tearline T may be formed in the top and rearpanels to define a removable tab adapted to be torn open to expose thecartons contents after the cover flap has been bonded to minor flaps F Fto form a closed carton.

Gusset folds G G G and G are suitably constructed at each corner of thetray or receptacle portion of the carton to form sealed corner closuresthereat. FIG. 3 illustrates partial formation of the blank whereas FIGS.4 and 5 illustrate complete formation of such tray portion by the FIG. 1apparatus.

Referring to FIGS. 1, 2, 6 and 7, feeding station 20 includes a cartonmagazine 23 comprising opposed pairs of upright'posts 24 and 25. Theposts are secured to frame 26 of the apparatus and adapted to retain aplurality of stacked carton blanks C therein along with the tapered endsof spaced, stationary supports 27. Each of the supports underlie andengage marginal rear edge portions of the lowermost blank to aid insupporting the blanks in the magazine. The tapered ends of such supportsare suitably positioned to permit the lowermost blank to be readilydisengaged therefrom by removal means 28, comprising a flexible suctioncup 29.

A flexible conduit 30 may be operatively connected to the suction cup ina conventional manner to communicate a negative pressure or vacuum (e.g.-5psi) thereto by means of a conventional vacuum source and The lowerend of the rod is slidably mounted in a sleeve member 35 pivotallymounted on a crank 36 by a pivot pin 37 (FIG. 9). The crank is attachedto a continuously rotating drive shaft 38 which is driven by a sprocket39. The gears are continuously driven by an endless chain 40 suitablymounted on sprockets 41-45. Sprocket 45 is mounted on a power shaft 46which is driven via conventional gear type transmission means by a maindrive motor 47 of the apparatus (FIG.

Thus it can be seen that actuation of motor 47 and drive shaft 46 willfunction to continuously move chain 40 to rotate sprocket 37. Uponsimultaneous rotation of crank 36, sleeve member 35 will reciprocate onrod 34 to oscillate stub shaft 33. Thus arm 32 will be pivoted betweenits dotted and solid line positions illustrated in FIGS. 7 and 9 tocontinuously remove a lowermost carton blank from the magazine. Astationary, laterally positioned guide wire 48 engages the edges of theblanks for aiding in such removal function.

The feeding station further includes vacuum belt conveying means shownas comprising spaced endless belts 50 and 51 (FIGS. 1, 6 and 7) havingapertures 52 and 53 formed therethrough, respectively. Belt 50, forexample, is mounted on a drive pulley 54 and idler pulley 55, the drivepulley being mounted on a drive axle 56 which is common to sprocket 41(FIG. 9). Belt 51 is mounted in a like manner to also be driven by driveaxle 56.

A hollow stationary support means or plate 57 is mounted below belt 50to support same (FIGS. 6 and 7 The portions of the support meansengaging the belt may have a Teflon or like coating formed thereon tolower the coefficient of friction therebetween. The support means formsvacuum chambers 58 therein adapted to be evacuated by means of a conduit59 communicating therewith. Such conduit communicates with vacuum source31 which may comprise a conventional centrifugal pump or the like (FIG.7). Vacuum belt 51 is supported on a similar support means or plate in alike manner.

Thus it can be seen that when the lower-most flat carton blank C, havingits forward edge only normally resting on belts 50 and 51, is pulleddownwardly onto the belts by vacuum cup 29 that such blank will besubjected to vacuum via apertures 52 and 53. The suction cup disengagesthe blank automatically due to the intermittent action of valve means(not shown) of control means 30a when it descends below the belts. Thusthe belts will function to grasp and move the blank toward formingstation 21 and between a pair of flexible pinch belts 60 and 61 and apair of nip rolls 62 and 63.

As best shown in FIGS. 6 and 7, the pinch belts are each suitablymounted on a plurality of spaced idler and take-up pulleys and aredriven by powered pulleys 64 and 65, respectively. Pulley 64 is drivenby a shaft 66, common to sprocket 43 (FIG. 9), whereas pulley 65 isdriven by a shaft 67 which is common to sprocket 44. Nip rolls 62 and 64are suitably mounted on and driven by shafts 66 and 67, respectively.

Referring to FIG. 6, the pinch belts and nip rolls deliver the cartonblank to a forming or female die 70 mounted on and having its formingchamber extending completely through a rotary table 71. Although eightsuch dies are shown, it should be understood that any desired numberthereof may be employed. As shown in FIG. the horizontally disposedtable is secured to an upstanding hollow column 72 rotatably mounted onspaced roller bearing assemblies 73 (one shown).

As schematically illustrated in FIG. 10, rotating column 72 is attachedto and driven by a bull sprocket 74 which, in turn, is driven by anendless chain 75. The chain is further trained on and driven by asprocket 76 secured to a drive shaft 77. The drive shaft is suitablydriven by drive shaft 46 which is driven by main electrical drive motor47 of the apparatus.

Referring to FIGS. 13 and 14, stationary finger-like guide wires 80, 81and 82 are suitably positioned to elevate and guide the blank onto theforming die. Flap F of the carton blank engages under a locating plate83 of locating means 83-88 to initiate the locating function. Uponcontinued rotation of the table flap R, will engage and be guided bylocating button 84 whereas flap F;; Will subsequently engage locatingbutton 85. Locating pins 86, 87 and 88 will assume the positionsillustrated in FIG. 14, relative to the blank, with locating pin 88functioning as the primary means for completely removing the blank frompinch belts 60 and 61.

Referring to FIGS. 11 and 12, turntable 71 and its associated formingmechanisms have been divided into sub-stations l-VIII for explanationpurposes. The upper heavy dotted line 89 schematically represents a camprofile exhibited during the carton forming operation.

7 The following operations approximately occur at such stations:

I. Flattened carton blank C initiates registry over forming die II. Amale die 90 cooperates with die 70 to form a pair of die means forpartially folding the carton blank therein;

III. The carton blank is further folded to ready gusset folds G Gthereof (FIG. 3) for bonding;

IV. Heat sealing means 91 and 92 discharge heated air onto the gussetfolds;

V. Die 90 begins its descent to compress gusset folds together to formtightly sealed corners;

VI. Die 90 moves downwardly, below the table, to permit the formedcarton to be ejected onto a discharge conveyor 93;

VII. Die 90 moves vertically upwardly; and

VIII. Die 90 is fully repositioned for a second carton formingoperation.

Referring to FIG. 8, each bank of heaters 91 and 92 may besimultaneously ignited by means of a spark plug 94 exposed to thecombustion chamber of one of the end heaters. Conduits then communicatethe ignited gaseous fuel mixture to all of the heaters. An ignitioncontrol system 95, comprising an on-off switch and 6,000V. electricaltransformer, selectively energizes the spark plug.

Referring to FIGS. 1 and 15, each male die 90 is secured to the end of arod 96, reciprocally mounted in spaced bearing journals 97 and 98. Suchbearing journals are secured to a bifurcated arm 99 which is, in turn,secured to rotatable column 72. A bracket 100 is attached to the upperend of the rod and has a roller 101 and a pair of rollers 102 rotatablymounted thereon.

Roller llllll is guided in its rotary movements by an endless cam track103, defining cam profile 89 in FIGS. 11 and 12, formed between spacedstationary bars 104 and 105. The cam track and rod 96 comprise actuatingmeans for linearly moving male die 90 into mating relationship withfemale die 70 for folding and forming the carton blank therein. Inboardrollers 102 preferably engage opposite sides of a vertically disposedguide means or bar 106 mounted on a bracket 107 attached to arm 99. Suchguide bar positively assures that rod 96 will only move vertically,without incurring any rotational or other extraneous movement.

As further illustrated in FIG. 15, dies and are each preferablycompletely jacketed therearound with chamber means 108 and 109,respectively, for circulating a coolant such as water therethrough forheat-sink purposes. As schematically illustrated therein, a pump 110 andvalve 111 may be utilized to selectively circulate and communicate suchcoolant through conduits 112, 113 and 114 and to chamber 109 of the maledie. Such fluid is then communicated from chamber 109 to chamber 108 ofthe female die via conduits 115 and 116. A conduit 117 returns the fluidto a heat exchanger 118 for recirculation purposes by means of pump 110.

Referring to FIGS. 6 and 15, opposed heat sealing means 91 and 92 eachcomprise a plurality of identical gas burner type nozzle means orheaters 120 positioned in arcuate arrays adjacent to table 71. Theheaters of heating means 91 and 92 are fixedly mounted on stationaryconduits 121 and 122, respectively, which function to communicate acombustible gaseous fluid, such as a commercially available naturalgas-air mixture, to the heaters. Such heaters and a conventional fuelsource and control means thereof are fully disclosed in US. Patentapplication Ser. No. 869,193 for Apparatus and Method for l-Ieat SealingCartons, filed on Oct. 24, 1969, by George Schafer et al. Suchapplication is assigned to the Assignee of this application.

As described therein each heater may be of the type identified as modelNo. 81-1-2 and manufactured by Selas Corp. of America. Such heatercomprises a metallic housing having a suitable refractory and insulativematerial formed therein to define a combustion chamber. As above stated,ignition means 94 and 95 function to ignite the gaseous fuelcommunicated to the combustion chambers by conduits 121 and 122. Due towell-known combustion and heat transfer phenomena, including theexpansion of the ignited gas-air mixture, a heated fluid stream 123(FIG. 15) is discharged from each heater and directed toward gussetfolds G,G.,. The heated fluid is discharged in sufficient volumes andmaintained within acceptable temperature and pressure ranges to activate(melt) the adhesive (e.g. polyethylene), but to prevent carbondistortion or scorching.

Through stations V and VI (FIGS. 6 and 12), cam track 103 (FIG. 15)functions to move rod 96 downwardly to fully fold and form the gussetfolds to bond or seal them together. At stations VI and VII the formedcarton is discharged onto conveyor means 93. Rod 96 thereafter movesupwardly through stations VII and VIII to ready male die 90 for asubsequent carton forming operation.

Referring to FIGS. 16-18, a carton stripping means 124 is preferablyutilized to positively strip the carton off each male die 90. Thestripping means comprises a bracket 125 bolted or otherwise suitablysecured to table 71. Upstanding guide bars 126 and 127 are secured tothe bracket and slidably mount a reciprocating member 128 thereon. Themember comprises parallel arms 129 and 130 secured thereto forengagement with the top edges of side flaps F and F of the carton.

Reciprocal movement is imparted to member 124 by means of a pin 131positioned in a lost motion slot 132 formed through the member. The pinis secured to a first lever arm 133 of a bellcrank mechanism furthercomprising a rockable shaft 134 having arm 133 and a second lever arm135 attached to opposite ends thereof. A roller 136 is rotatably mountedon a pivot pin 137, secured to arm 135, to engage a stationary cam track138 mounted below table 71.

A coil portion 139 of a biasing spring is mounted on shaft 134 and hasone end anchored to a housing 140. The housing, journalling shaft 134therein, is secured to bracket 125. The other end or finger portion 141of the spring engages arm 135 to constantly urge roller 136 against camtrack 138.

Thus it can be seen that upon rotation of table 71, through stations VIand VII, that the roller will engage the cam track to rock shaft 134 tomove member 128 downwardly to its dotted lined position in FIGS. 16 and17. Thus arms 129 and 130 will engage flaps F and F of the carton tostrip it off male die 90. The formed carton will then be deposited ontomoving conveyor 93 wherefrom it may be transported to a frozen foodfilling and final sealing apparatus. Suitable drive mechanisms (notshown) may be employed to drive the conveyor via the apparatus maindrive motor.

FIGS. 19-20 illustrate a heater assembly, similar to that shown in FIGS.6, 8, l2 and 15, comprising a plurality of heaters 120a connectedtogether in series. As mentioned above, us. Patent application Ser. No.869,193 fully discloses such heaters. In particular, each heater has atubular neck 200 which is threadably attached to a conduit or manifold120a adapted to have a gaseous, combustible fuel communicated therein bymeans of an inlet 201.

Such fuel is communicated to a chamber means 202 formed in each heatervia tubular neck 200 and orifices 203. The orifices are formed throughrefractory material 204 which is suitably fon'ned in a metallic housing205. A tubular member 206, defining a passage 207 therethrough, issecured to one heater and extends laterally therefrom in close proximityto a next adjacent heater, having a port 208 formed through a sidewallthereof.

Thus, chamber means 202 of each adjacent pair of heaters communicate bypassage means comprising passages 207 and 208. A nut 209 is threadablymounted on tubular member 206 and has a face 210 thereof adapted to bemoved axially into abutting relationship with an outside wall of asecond adjacent heater and in circumventing relationship with port 208to form a static seal therearound. In FIG. 19, such nuts are shown in anon-sealing position prior to their rotation on members 206 to effectsuch static seals.

In addition, it should be noted that passages 207 and ports 208 of allof the heaters are preferably positioned in linear relationship topermit expeditious communication of the gaseous fuel to chamber means202. As further shown in FIG. 19, a first one of the heaters has ahousing 211 secured thereto, mounting ignition means in the form of aspark plug 94a thereon. The housing defines a pre-ignition chamber 212which communicates with chamber means 202 of the first heater, via asecond port 213 formed through a sidewall thereof.

As mentioned above, an ignition control system 95a, comprising an on-offswitch 214 and an electrical transformer 215, is arranged to selectivelyenergize the spark plug. Such energization ignites the gaseouscombustible fuel communicated to chamber 212 which in turn substantiallysimultaneously ignites the gaseous fuel contained in all chamber means202 to provide a heated fluid discharged through nozzles 216. A ventingorifice 217 is preferably formed through housing 211, closely adjacentto the spark plugs electrode, to provide an air vent thereof aiding incombustion.

What is claimed is:

1. In a carton forming apparatus comprising a plurality of heaters eachcomprising a combustion chamber means formed therein and an elongated,restricted gas orifice communicating with said combustion chamber meansfor discharging a heated fluid therefrom, said heaters mounted closelyadjacent to each other to align said restricted gas orifices, fuelsupply means for communicating a combustible gaseous fuel to each ofsaid chamber means, passage means communicating all of said combustionchamber means with each other and ignition means for substantiallysimultaneously igniting said gaseous fuel in all of said combustionchamber means, means for moving folded flaps of a carton blank closelyadjacent to the aligned restricted gas orifice of said heaters and meansfor sealing said flaps together.

2. The invention of claim 1 wherein said ignition means is exposed onlyto one of said combustion chamber means.

3. The invention of claim 1 wherein said fuel supply means comprises aconduit having said heaters removably attached thereon.

4. The invention of claim 1 wherein at least one of said heaters has atubular member secured thereon to extend laterally therefrom in closeproximity to a next adjacent second heater, said passage meanscomprising a port formed through a sidewall of said next adjacent heatercommunicating with the chamber means of said one heater through saidtubular member.

5. The invention of claim 4 further comprising a nut threadably mountedon said tubular member and having a face thereof abutting an outsidewall of said second heater in circumventing relationship with said portto form a static seal therearound.

6. The invention of claim 2 wherein said ignition comprises a spark plugmounted on a housing attached to said one heater, said housing having anignition chamber formed therein communicating with the chamber means ofsaid one heater.

7. The invention of claim 6 further comprising means forming a ventingorifice through a sidewall of said housing, adjacent to an electrode ofsaid spark plug.

8. The invention of claim 6 further comprising an ignition controlmeans, including an electrical transformer and an on-ofi switch,operatively connected to said spark plug for selectively energizingsame.

, UNITED STATES PATENT VIOFFICIE CERTIFICATE OF CORRECTION Patent No. 73, 7, I Dated June 97 Inventor(s) Alfred B. LeFebvre et a1 It iscertified that error appears in the above-identifieipatent and that saidLetters Patent are hereby corrected as shown below:

I Column 8, line 1 of claim .6, after "ignition" insert --meens--.

Signed and sealed this 19th day of November 1974 (SEAL) Attest:

MCCOY M. GIBSON JR. n C. MARSHALL DANN Attesting Officer 7 Y 1 vCommissioner of Patents FORM Po-1oso (10-69) f USCOMMDC Wanda U. 5.GOVERNMENT PRINTING OFFICE 1969 O-366-334

1. In a carton forming apparatus comprising a plurality of heaters eachcomprising a combustion chamber means formed therein and an elongated,restricted gas orifice communicating with said combustion chamber meansfor discharging a heated fluid therefrom, said heaters mounted closelyadjacent to each other to align said restricted gas orifices, fuelsupply means for communicating a combustible gaseous fuel to each ofsaid chamber means, passage means communicating all of said combustionchamber means with each other and ignition means for substantiallysimultaneously igniting said gaseous fuel in all of said combustionchamber means, means for moving folded flaps of a carton blank closelyadjacent to the aligned restricted gas orifice of said heaters and meansfor sealing said flaps together.
 2. The invention of claim 1 whereinsaid ignition means is exposed only to one of said combustion chambermeans.
 3. The invention of claim 1 wherein said fuel supply meanscomprises a conduit having said heaters removably attached thereon. 4.The invention of claim 1 wherein at least one of said heaters has atubular member secured thereon to extend laterally therefrom in closeproximity to a next adjacent second heater, said passage meanscomprising a port formed through a sidewall of said next adjacent heatercommunicating with the chamber means of said one heater through saidtubular member.
 5. The invention of claim 4 further comprising a nutthreadably mounted on said tubular member and having a face thereofabutting an outside wall of said second heater in circumventingrelationship with said port to form a static seal therearound.
 6. Theinvention of claim 2 wherein said ignition coMprises a spark plugmounted on a housing attached to said one heater, said housing having anignition chamber formed therein communicating with the chamber means ofsaid one heater.
 7. The invention of claim 6 further comprising meansforming a venting orifice through a sidewall of said housing, adjacentto an electrode of said spark plug.
 8. The invention of claim 6 furthercomprising an ignition control means, including an electricaltransformer and an on-off switch, operatively connected to said sparkplug for selectively energizing same.